Es. Jung et al., SIMULTANEOUS DETERMINATION OF IBUPROXAM AND IBUPROFEN IN HUMAN PLASMABY HPLC WITH COLUMN-SWITCHING, Chromatographia, 37(11-12), 1993, pp. 618-622
A new high-performance liquid chromatographic method with column switc
hing has been developed for the simultaneous determination of Ibuproxa
m and its metabolite Ibuprofen in plasma. The plasma samples were inje
cted onto a LiChrosorb RP-8 precolumn after dilution with an internal
standard solution in phosphoric acid. Polar plasma components were elu
ted with 0.05 M phosphoric acid. After valve switching, the concentrat
ed drugs were eluted in the back-flush mode and separated on an Inerts
il ODS-2 column with acetonitrile-methanol-phosphate buffer as mobile
phase. The method showed excellent precision, accuracy and speed with
detection limit of 0.1 mug ml-1. Total analysis time per sample was le
ss than 30 min and the coefficients of variation for intra and inter-a
ssay were less than 3.5 %. This method has been successfully applied t
o plasma samples from human volunteers after oral administration of Ib
uproxam.